Build an ADU in Hampton Falls.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Hampton Falls — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.
4 districts
Each district's single-family setbacks — which your ADU follows. The primary residential district is highlighted.
Verified against the official Hampton Falls zoning ordinance · source · 2026-07-07
- Front
- 50 ft
- Side
- 50 ft
- Rear
- 50 ft
- Max coverage
- 15% impervious
- Min lot
- 87,120 sf (~2.00 ac)
Default district: every parcel not listed in the TCD/BDS/BDN tax-map parcel lists is in the A District (Art II Sec 2.1). EXEMPTION: lots of record of 1 acre (43,560 sf) or less need only 25 ft from all lot lines (7.7.1); contiguous additions to existing closer-than-50-ft…
- Front
- 15 ft
- Side
- 10 ft
- Rear
- 15 ft
- Max coverage
- 65% impervious
- Min lot
- 32,000 sf (~0.73 ac)
Mixed-use downtown district around the historic Town Common; parcels enumerated by 2013 tax map/lot in Art II 2.1.1. From the Sec 5 Table of Dimensional Requirements: min lot 32,000 sf; front 15 ft; rear 15 ft; side 10 ft; lot coverage max 65% ('Lot Coverage' is defined…
- Front
- 20 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 70% impervious
- Min lot
- 43,560 sf (~1.00 ac)
Adopted March 2014; parcels enumerated by 2013 tax map/lot in Art II 2.1.2. From the Sec 5 Table of Dimensional Requirements: min lot 1 acre (43,560 sf); front 20 ft; rear 20 ft; side 20 ft; lot coverage max 70% (impervious basis per the 2014 'Lot Coverage' definition); min…
- Front
- 25 ft
- Side
- 25 ft
- Rear
- 25 ft
- Max coverage
- 75% impervious
- Min lot
- 87,120 sf (~2.00 ac)
Adopted March 2014; light industry/retail/commercial district near highway access; parcels enumerated by 2013 tax map/lot in Art II 2.1.3. From the Sec 5 Table of Dimensional Requirements: min lot 2 acres (87,120 sf); front 25 ft; rear 25 ft; side 25 ft; lot coverage max 75%…
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Hampton Falls ADU FAQ
Yes. Under NH RSA 674:71-73 (HB 577), one accessory dwelling unit is allowed by-right on single-family lots statewide, including Hampton Falls (Rockingham County). A detached ADU can be up to 950 sf.
In Hampton Falls's A zone, ADUs follow the single-family setbacks: 50 ft front, 50 ft side, and 50 ft rear. Hampton Falls has 4 zoning districts in total — see the full table below. Confirm your exact zone with the town.